Intel E3-1260L CM8062301061800 User Manual
Product codes
CM8062301061800
Datasheet, Volume 1
25
Interfaces
2.1.5.3
Out-of-Order Scheduling
While leveraging the Just-in-Time Scheduling and Command Overlap enhancements,
the IMC continuously monitors pending requests to system memory for the best use of
bandwidth and reduction of latency. If there are multiple requests to the same open
page, these requests would be launched in a back to back manner to make optimum
use of the open memory page. This ability to reorder requests on the fly allows the IMC
to further reduce latency and increase bandwidth efficiency.
the IMC continuously monitors pending requests to system memory for the best use of
bandwidth and reduction of latency. If there are multiple requests to the same open
page, these requests would be launched in a back to back manner to make optimum
use of the open memory page. This ability to reorder requests on the fly allows the IMC
to further reduce latency and increase bandwidth efficiency.
2.1.6
Memory Type Range Registers (MTRRs) Enhancement
The processor has 2 additional MTRRs (total 10 MTRRs). These additional MTRRs are
specially important in supporting larger system memory beyond 4 GB.
specially important in supporting larger system memory beyond 4 GB.
2.1.7
Data Scrambling
The memory controller incorporates a DDR3 Data Scrambling feature to minimize the
impact of excessive di/dt on the platform DDR3 VRs due to successive 1s and 0s on the
data bus. Past experience has demonstrated that traffic on the data bus is not random
and can have energy concentrated at specific spectral harmonics creating high di/dt
that is generally limited by data patterns that excite resonance between the package
inductance and on-die capacitances. As a result, the memory controller uses a data
scrambling feature to create pseudo-random patterns on the DDR3 data bus to reduce
the impact of any excessive di/dt.
impact of excessive di/dt on the platform DDR3 VRs due to successive 1s and 0s on the
data bus. Past experience has demonstrated that traffic on the data bus is not random
and can have energy concentrated at specific spectral harmonics creating high di/dt
that is generally limited by data patterns that excite resonance between the package
inductance and on-die capacitances. As a result, the memory controller uses a data
scrambling feature to create pseudo-random patterns on the DDR3 data bus to reduce
the impact of any excessive di/dt.
2.2
PCI Express* Interface
This section describes the PCI Express interface capabilities of the processor. See the
PCI Express Base Specification for details of PCI Express.
PCI Express Base Specification for details of PCI Express.
The number of PCI Express controllers is dependent on the platform. Refer to
Chapter 1
for details.
2.2.1
PCI Express* Architecture
Compatibility with the PCI addressing model is maintained to ensure that all existing
applications and drivers operate unchanged.
applications and drivers operate unchanged.
The PCI Express configuration uses standard mechanisms as defined in the PCI
Plug-and-Play specification. The initial recovered clock speed of 1.25 GHz results in
2.5 Gb/s/direction that provides a 250 MB/s communications channel in each direction
(500 MB/s total). That is close to twice the data rate of classic PCI. The fact that
8b/10b encoding is used accounts for the 250 MB/s where quick calculations would
imply 300 MB/s. The external graphics ports support Gen2 speed as well. At 5.0 GT/s,
Gen 2 operation results in twice as much bandwidth per lane as compared to Gen 1
operation. When operating with two PCIe controllers, each controller can be operating
at either 2.5 GT/s or 5.0 GT/s.
Plug-and-Play specification. The initial recovered clock speed of 1.25 GHz results in
2.5 Gb/s/direction that provides a 250 MB/s communications channel in each direction
(500 MB/s total). That is close to twice the data rate of classic PCI. The fact that
8b/10b encoding is used accounts for the 250 MB/s where quick calculations would
imply 300 MB/s. The external graphics ports support Gen2 speed as well. At 5.0 GT/s,
Gen 2 operation results in twice as much bandwidth per lane as compared to Gen 1
operation. When operating with two PCIe controllers, each controller can be operating
at either 2.5 GT/s or 5.0 GT/s.
The PCI Express architecture is specified in three layersTransaction Layer, Data Link
Layer, and Physical Layer. The partitioning in the component is not necessarily along
these same boundaries. Refer to
Layer, and Physical Layer. The partitioning in the component is not necessarily along
these same boundaries. Refer to
Figure 2-2
for the PCI Express Layering Diagram.